This invention relates to the art of drain cleaning apparatus and, more particularly, to an improved feed control arrangement by which a flexible snake of such apparatus can be axially advanced and retracted relative thereto during a drain cleaning operation.
The present invention finds particular utility in connection with portable, motor driven flexible snake-type drain cleaning apparatus of the character in which the snake is rotated by a hand held, trigger actuated motor, such as shown for example in U.S. Pat. No. 4,956,889 to Kirk. The patent to Kirk is assigned to the same assignee as the present invention, and the disclosure thereof is incorporated herein by reference. While the invention will be described in detail hereinafter in conjunction with such hand held, motor driven drain cleaning apparatus, it will be appreciated that the invention is applicable to other power driven drain cleaning apparatus in which feed control arrangements are provided for axially advancing and retracting the snake during use of the apparatus.
The drain cleaning apparatus disclosed in the patent to Kirk is comprised of a hand held, trigger actuated motor drivingly connected to a snake housing for rotating the housing about a longitudinal axis. The housing is provided with a guide tube which opens thereinto coaxial with the axis, and a flexible snake is coiled within the housing and extends through the guide tube and, generally, is provided on its free end forwardly of the guide tube with a blade or other auger component. Often, the housing or a snake cartridge within the housing can be removed to facilitate connecting successive snakes for feeding into a waste line or for using different diameter snakes with the apparatus. The snake, as is conventional, is an elongate, flexible member made of tightly wound spring wire, and the free outer end thereof is adapted to be pulled from or pushed back into the housing in which the snake is stored during periods of non-use. A hand grip sleeve arrangement surrounds the guide tube and is rotatable and axially displaceable relative to the guide tube to effect the displacement of snake clamping elements into engagement with the snake to preclude axial displacement of the snake relative to the guide tube and housing, whereby the operator can forcibly displace the apparatus and thus the snake axially relative to the drain pipe into which the snake extends.
Hand held, motor driven drain cleaners of the foregoing character have also been provided with arrangements for axially feeding and retracting the snake relative to the drum in response to rotation of the snake as shown, for example, in U.S. Pat. Nos. 3,224,024 to Hunt and 5,029,356 to Silverman, et al. In the patent to Hunt, the front end of the drain cleaning apparatus is provided with an attachment comprising a pair of helically grooved feed rolls against which the snake is pressed by an actuator block or actuator rolls displaced by a pivotal lever. Engagement of the rotating snake with the helical rolls results in axial displacement of the snake relative to the device. In the patent to Silverman, et al., the drive arrangement comprises a plurality of rolls spaced apart about the snake and having axes which are skewed relative to the snake axis and wherein the rolls are cammed radially inwardly to engage with the rotating snake to achieve axial feeding thereof relative to the device. Other snake feeding devices used in connection with power driven drain cleaners which, while portable, are not of the hand held type, are shown for example in U.S. Pat. Nos. 4,580,306 to Irwin, 5,031,263 to Babb, et al. and 5,239,724 to Salecker, et al.
In all of the feed control arrangements heretofore available for use in connection with power driven drain cleaning apparatus, including those specifically referenced above, the control arrangements are structurally complex, difficult to access with respect to cleaning and/or performing maintenance and replacement operations with respect to parts thereof, and require time-consuming adjustments or disassembly operations in connection with the initial feeding of the enlarged auger contoured end of the snake or an auger or blade attachment thereon through the feed device. In this respect, for example, the feed rolls are enclosed in a housing and cannot be accessed for cleaning, maintenance or replacement without at least partial disassembly of the housing, or removal of the rolls, whereby access in any event requires considerable time and effort. In all of the arrangements in which the feed rolls are radially adjustable relative to an opening through the housing which receives the snake, the supporting structures are complex, adjustment is time-consuming and displacement of the rolls radially outwardly of the opening to accommodate withdrawal or insertion of the auger tip of a snake is time-consuming, especially if it is necessary to remove one of the feed rolls. With regard in particular to a hand held drain cleaning device of the character disclosed in the patent to Hunt referred to above, the location and disposition of the lever makes it difficult to achieve stability with respect to holding the drain cleaner and operating the lever to apply sufficient force on the snake to achieve feeding thereof, especially when an obstruction is encountered in the drain line.